I got it for $ 45 used, It has one 7 inch circular plate with two mounted blades, I may be wrong on this but a lawn edger blade cut down should work to chop up the cardboard. Thanks, Frank this will get me working tomorrow on getting an edger blade. If not, back to the drawing board. This is an older model with only one place to shred with. I got an old electric lawn edger that has a blade and a 1.25 HP motor. Maybe this should work.

I heard one theory about building a circle of sticks and then burying them with compost. The logic being that the branches would create air space. I tried it once, I don't think it made a difference either way. I use my sticks for kindling though.